This invention relates to a method and device for adjusting the distance between inner and outer bearing assemblies of a wheel hub to assure proper and consistent alignment.
Typically, a wheel assembly will include inner and outer bearing assemblies to support rotation of a wheel hub about a spindle. A nut threaded onto corresponding threads of the spindle secures the wheel hub between bearing assemblies such that the wheel hub freely rotates on the bearing assemblies. The nut is fastened with sufficient torque to apply a predetermined amount of pressure to the bearing assemblies in order to properly support the wheel hub. Insufficient torque can cause misalignment of the wheel hub and premature wear on the bearing assemblies and excessive torque can cause excessive heat build up and damage to the bearing assemblies.
It is known in the art to provide a spacer between the inner and outer bearing assemblies to maintain a predetermined space between the inner and outer bearing assemblies no matter what torque is applied to the nut. The spacer is designed to be essentially incompressible under any load that can be exerted by tightening of the nut. The spacer, wheel hub and bearing assemblies are then assembled to the spindle where the nut is tightened to secure the wheel hub.
The spacer in such assemblies forms a cavity about the spindle. A leak resistant seal is formed between the bearing assemblies and the spacer because of the pressure exerted by the nut. The wheel hub is filled with lubricant for the bearings assemblies. The pressure between the spacer and the bearings prevents fluid from entering the cavity as the wheel hub is filled with lubricant. The result is that the level of lubricant is artificially high because of the empty unfilled space of the cavity. The lubricant reaches a fill line indicating that the wheel hub has been filled with the proper amount of lubricant, without actually having the required amount. The leak resistant seal between the spacer and the bearing assemblies allows lubricant to slowly enter the cavity thereby dropping the lubricant level. Insufficient lubricant in the wheel hub can lead to premature bearing assembly wear and failure.
For these reasons, it is desirable to develop a spacer to set the distance between bearing assemblies that will accommodate the proper lubrication of the bearing assemblies.